I have tried in HFSS 14.0, but it is not working. I have made one port magnitude as zero watts and another port magnitude as 1 watt. Still I am getting s(2,2), s(1,2) and s(2,1) along with s(1,1)....... Is there any settings to be done further?
When you Simulate antenna with dual (or multi) ports, you get S-parameters (or active S11, S22,...) based on excitation of one port and the power will flow to other ports of absorb to imperfect dielectric and metal or Radiation boundary.